Spin injection from epitaxial ferromagnetic films into GaAs

✍ Scribed by M. Ramsteiner

• Book ID: 104305689
• Publisher: Elsevier Science
• Year: 2002
• Tongue: English
• Weight: 390 KB
• Volume: 63
• Category: Article
• ISSN: 0167-9317
• DOI: 10.1016/s0167-9317(02)00600-7

✦ Synopsis

Electrical injection of spin polarized electrons is observed at ferromagnet-semiconductor interfaces by analyzing the electroluminescence signal of GaAs /(In,Ga)As light emitting diodes (LED) covered with the metals Fe or MnAs. The circular polarization degree of the emitted light reveals a spin polarization for recombining electrons of about 2%. Time-resolved data on spin relaxation times indicate that the actual spin injection efficiency from Fe into GaAs is about 5% at room temperature. The underlying injection mechanism is explained in terms of a tunneling process.